Kiwifruit and quince KLBs showed a decrease of TTA in comparison
with the corresponding FJs. The high TTA observed in kiwi
and quince FJs was mainly due to malic and quinic acid, as well as
citric acid as reported by Sch€afer and Hossain (1996) and Silva et al.
(2004). The decrease is explained by the consumption of organic
acids during the fermentation process at 25 C (Puerari et al., 2012).
Furthermore, the ability to ferment and assimilate the organic
acids, as carbon and energy sources, causes an increase of pH value
(Lopandic et al., 2006). However, the increase of TTAwas registered
in some KLBs. Since an increase in pH and TTA has been observed in
some fruits during the storage under different thermal regimes (da
Silva et al., 2013), it might be supposed that the results displayed by
apple, grape and pomegranate KLBs are imputable to the extraction
of organic acids from the residual part of pulp still present in the
juices during fermentation.